Fire detector



FIG. 1 is a perspective view of a fire detector showing my new design;

FIG. 2 is an elevation of the fire detector of FIG. 1;

FIG. 3 is a bottom view of the fire detector of FIG. 1; and,

FIG. 4 is a front view of the fire detector of FIG. 1. 

The ornamental design for a fire detector, as shown and described. 